Multiple grooving of pavement

ABSTRACT

Wet cutting of pavement into multiple grooves to impart antiskid properties thereto produces a slurry of solid particles in water. In treatment prior to disposal of the slurry, particles of cutting material are reclaimed from the slurry for subsequent reuse, and pavement particles are recovered optionally therefrom. Mobile equipment is provided for accomplishing such multiple grooving of pavement and such reclamation or recovery of particulate material.

Zuzelo MULTIPLE GROOVING OF PAVEMENT [76] Inventor: Edward A. Zuzelo, 654'Broad Acres Rd., Narberth, Pa. 19072 22 Filed; June 13, 1972. 21 Appl. No.: 262,219

[51] Int. Cl. E0lc 23/09 [58] Field of Search 299/394l; 51/264, 270

[56] 1 References Cited UNITED STATES PATENTS 3,572,841 3/1971 Rhodes 299/39 3,598,446 8/1971 Hatchet 2,771,718 11/1956 Gustafson etal 7 1 Z N 1 i I l I I i L.

HYDR. i DRIVE 1 ENGINE 1 1451 Apr. 9, 1974 2,905,266 9/1959 Poch 1.. 51/270 X Primary Eraminer-Ernest R. Purser Attorney, Agent, or F irmSeidel, Gonda & Goldhammer [5 7] ABSTRACT Wet cutting of pavement into multiple grooves to impart antiskid properties thereto produces a slurry of solid particles in water. In treatment prior to disposal of the slurry, particles of cutting material are reclaimed from the slurry for subsequent reuse, and pavement particles are recovered optionally therefrom. Mobile equipment is provided for accomplishing such multiple grooving of pavement 'and suchv reclamation or-recovery of particulate material.

16 Claims, 5 Drawing; Figures WENTEDAFR 9 m4 saw 1 or 2 /J GEN. DRIVE CLEAN 51f SLURRYING FIRST SECOND -5 us eo SEPARATION WATER WATER AND PICKUP ff SECOND v a,

f PICKUP DIAMOND. SLUDGE f WASH SHEET 2 BF 2 PATENTED APR 9 1974 MULTIPLE GROOVING QF PAVEMENT This invention relates to multiple grooving of pave- -ment to improve traction for vehicles thereon, such as rectional control and stopping ability, especially during wet weather when the wheels of cars and airplanes tend to hydroplane or slide on a thin film of water on the pavement. Such grooves, which usually extend longitudinally in roadways and transversely in runways, not only reduce the amount of water standing on the pavement surface but also provide ready escape paths for such water whenencountered by the vehicle wheels.

Unfortunately there are potential safety hazards inherent in the. grooving operation itself and its after math. Thus, dryjcutting produces clouds of dust detrimental to visibility and tothe health of workmen and other persons in the vicinity. Being relatively slow, dry

cutting also impedes traffic for substantial periods of time. On the other hand, wet cutting produces a slurry liquid used to lubricate the cutting blades, and a coating of such slurry renders the pavementslippery. Both methods leave particulate residues that may be dislodged byrain or high winds (or jet airplane exhausts) and thereby produce a further traffic hazard.

A primary object of the present invention is elimination of safety hazards attendant upon or consequent to multiple grooving of pavement.

Another object is improvement in efficiency of multiple grooving of pavement.

A further object is more economical multiple grooving of-pavement.

Other. objects of this invention, together with means and methods for attaining the various objects will be apparent from the following description and the accompanying diagrams. r i a FIG. 1 is a partially schematic side elevation of amachine useful accordingto the present invention in the multiple grooving of pavement;

FIG. 2.-is a similar view of auxiliary apparatus shown in trailer form; I

FIG. 3 is an enlarged side sectional elevation of a detail of FIG. 1.;

FIG. 4 is a sectional plan taken at IV-IV and y FIG. 5 is a schematic flow diagram applicable to the foregoing in the practice of this invention.

In general, the objects of the present invention are accomplished, in multiple grooving of pavement to improve traction thereon when wet, wherein particles of pavement material and cutting material result from grooving engagement of. cutting means with the pavement at a cutting location, by slurrying such resulting particles with water supplied to the cutting location and collecting the resulting slurry for subsequent treatment and disposal. Reusable particles of slurried cutting material are reclaimed, such as centrifugally, from the slurry for subsequent reuse. Also, pavement particles are optionally recovered likewise therefrom before dis posal of at least part of the residual slurry or components thereof at a remote location.

of FIG. 3;

FIG. 1 shows steerable machine having a set of front wheels 13 and a set of rear wheels 15 (only one of each'being visible) on pavement 1 and having frame 11 supported by the wheels and carrying thereon additional components. Shown in block form on the frame at the front are engine 14 and, driven directly by the engine, generator 16 and hydrostatic drive 17. Connected to the generator by suitable electrical leads is motor 1 8, which drives pump 19, shown in block form on the frame at the rear of the machine. Suspended under the midportion of the frame on retractable support 21 is cutting assembly 20, which is shown fragmentarily in greater detail in FIGS. 3 and 4. Blocked out above the midportion of the frame is a region in which mechanism for retracting and extending or otherwise moving the cutter assembly is located; such mechanism is not shown because it does not form any part of the present invention, and such conventional mechanism as a handwheel worm arrangement may be used to raise and lower the cutter assembly. Alternatively, more sophisticated mechanism for raising or retracting and for lowering or extending the cutter assembly may be employed in conjunction with this invention.

Hydrostatic drive 17, which is shown connected to the front wheels by fluid line 30, preferably is of dualspeed type, such as is well known, capable of providing a suitable over-the-road speed for transport between working sitesand a crawl speed for on-site operation. Fluid line 31 connects the hydrostatic 'drive to the cut-. ter assembly to rotate the cutting discs or blades. Suit able hydraulic motors to which lines and 31 connect to drive the machine and the cutter assembly, respectively, are not shown but are constructed and connected to the wheel axle and thecutter shaft as is well known in the art. Alternatively, the machine may be driven by mechanical coupling to the engine through suitable reduction gearing, and the cutter assembly may be rotated by similar mechanical interconnection; or, if desired, either or bothdrives may beelectric, from one or more engine-driven]generators or alternators.'lt will be apparent, 'of course, that although frontwheel drive is indicated for the machine itself, that the rear wheels may be. driven instead of or in addition to the front wheels. This invention is independent of any particular form of drive of the machine itself or of the cutter assembly, being useful with any suitable forms of drive. 7

Pump 19 is of dual type, pumping water from a source (located separately) to the cutter assembly through line 32 and pumping resulting slurry from the cutter assembly through return line 34 to a storage 10- cation (also located separately) as indicated by arrows. FIG. 2 shows trailer 40 with bed 41 supported on front wheels 43 and rear wheels 45 (only one of each being visible) and carrying reservoir or source tank 42 with inlet 46 for clean water and storage tank 44 with outlet 48 for the slurry or more specifically for used water from the slurry. Normally closed valve 50 may be opened to interconnect the source tank and the storage tank if andwhen desired. Lines 32' from the clean water source tank and return line 34 to the storage tank are readily attachable to and detachable from respective lines 32 and 34 on the machine of FIG. 1 by means of the fittings shown terminating the lines. Interposed between the return line and the storage tank are two centrifugal separators of conventional hydrocyclone type. i

First separator 51 receives slurry from the cutter assembly through line 34, which constitutes the hydrocyclone feed line; thehydrocyclone underflow passes into compartment 53 thereunder, while the overflow passes through line 35 (containing an appropriate pump) to second separator 52, for which it constitutes the hydrocyclone feed line. The underflow from the second separator passes into compartment 54 thereunder, while the overflow passes through line 36 into storage tank 44. First compartment 53 has line 55 (with pump) for fresh water from source tank 42 entering the top and has line 56 (with pump and check valve) for used water leaving the bottom and joining line 35 leading to the second separator. Second compartment 54 has line 58 from the bottom joining line 65 (with dual pump at the junction), which in turn (with check valve) joins line 36 leading to storage tank 44. The respective compartments are openable on the opposite side (not shown) and optionally on the visible side also to facilitate removal of the underflow materials accumulated therein.

Supported underneath the midportion of trailer bed 41 is brush assembly 60, comprising cylindrical rotary brush 62 protruding into contact withthe pavement underneath surrounding shroud 63. Line 64 (with pump) leads from water source tank 42 to jets 68 (one visible) directed from the rear toward the conjunction of the brush with the pavement, while return line 65 (with pump) from an interior trough (not visible) formed within the bottom of the shroud joins line 58 leading to first separator 51 as aforementioned. Drive chain (or belt) 69 from the rear wheels to the brush rotates it in a direction opposite to the direction of travel of the trailer. It will be understood that the trailer is designed to be detachably secured, as by the indicated mating hitches, to machine to be pulled thereby. The various pumps on the trailer are provided with electrical leads (not shown) to connect with connectors 37 located at the rear of frame 11 of the machine and terminating the-illustrated electrical leads from the generator. 1 FIGS. 3 and 4 show cutter assembly of FIG. 1 on an enlarged scale, in side sectional elevation and sectional plan, respectively. Horizontal shaft 70 is supported at its ends by yoke 21 on retractable support 21 and carries, spaced equally along the shaft and transversely of the machine itself, a multiplicity of cutting discs or blades 71 detachably secured thereto between spacers 72. Shroud 74 of generally involute crosssectional form has end plate 76 and encloses the blades above the pavement, being closer to the blades at the front and further therefrom at the rear. Except directly under the blades the shroud is closed underneath at the front by relatively small sloping trough 73 connected to return line 33, and at the rear by relatively large sloping trough 75 connected to return line 38. Underneath the rear trough is a multiplicity of jet nozzles 78 fed from manifold 77, which is connected by line 79 to clean water line 32. The nozzles are spaced under and between adjacent blades and direct the water sideways and forward against the blades and toward the cutting junction of the blades with pavement l, in which they are forming multiplicity of grooves 100 (one visible). It will be understood that the rotation of the blades against the forward direction of movement of the machine carries the water (and particles of pavement and I of cutter material, which become slurried therewith) forward at the bottom and upward and toward the rear within the shroud to collect mostly in the rear trough and to a lesser extent in the front trough, from both of which the collected slurry is pumped to the first separator for centrifugal treatment therein.

Operation of the described and illustrated apparatus to practice the present invention is readily understood, especially with further reference to the simplified flow diagram of FIG. 5, in which the blocks represent process steps or stations and the interconnecting lines are numbered in accordance with the foregoing. Thus, the machine is operated to move forward slowly and to rotate the blades relatively rapidly to cut a multiplicity of shallow parallel grooves closely spaced and extend ing in the longitudinal direction of machine movement. Clean water is supplied, as from source tank 42, to a cutting assembly, such as assembly 20, at the cutting location. There the water is slurried with particles of pavement removed by the abrasive cutting and with particles of cutting material (chiefly diamonds) dislodged from the blades themselves.

The resulting slurry is picked up and forwarded to the first stage of centrifugal separation, as in first separator 51, wherein the diamond (or other relatively dense) particles of cutter material are segregated in the underflow, while the less dense pavement particles pass out in the overflow. The underflow is washed with additional clean water. in a conventional filtration step, as in diamond wash'compartment 53, optionally with mechanical agitation of the filter elements (usually fine metallic screens). Thereafter, that wash water is added to the overflow from the first separation, which then constitutes the feed for the second separation. Of course, the diamonds or other dense cutting particles are recovered manually from the compartment at suitable intervals, for reuse in manufacture of additional cutter blades or for other appropriate use.

In further centrifugal separation, as in second separator 52, the pavement particles are segregated in the underflow, in the form of a damp sludge. Some water may be extracted from the sludge and be pumped away, as to used water storagetank 44, where the overflow from the second separation also goes. Sludge accumulates, as in sludge compartment 54, from which it is removed manually at appropriate intervals for disposal at a remote site-either wet or after drying, whereupon the resulting caked powder is suitable for use as a filler in various cementitious construction materials or the like. Particulate material not picked up at the cutting location is preferably subjected to a second pickup step, as the trailer passes thereover, through appropriate brushing action, as by action of brush assembly 60, and supplying of additional slurrying water to the brushing location. The resulting slur ry is fed to a first centrifugal separation step, as in separator 5l,'along with the slurry from the cutting location. v

The entire process is continuous and can continue until all the clean water has been used, whereupon most of it will have collected in the storage tank in the form of used water, i.e., containing unseparated pavement particles and perhaps a slight amount of cutter material in particulate form, together with oil, rubber, soil and the like removed from the pavement surface. At such time the trailer may be detached from the machine and be replaced by another trailer having a full tank of clean water and an empty tank for used water, as well as clean compartments for diamonds and for sludge. Alternatively, especially where the pavement being grooved is" sufficiently new not to have-been coated heavily with oil, rubber, soil, etc., the clean water and used water tanks may be interconnected by opening the valve therebetween (as suggested by the broken line in FIG. 5), in which event the overall'process can be practiced as a closed system, subject to gradual loss of water because of incomplete pickup and gradual increase in unseparated solids concentration. If desired, additional stages of separation may be added to facilitate such recycling, as is especially useful where it is inconvenient, uneconomical, or otherwise imprac ticable to exchange trailers. In some locations, for example, a source of clean water or an appropriate disposal location for sludge or used water may be too re mote to permit single cycling of the water.

Regardless of whether operated in single-cycle or recycle fashion, the present invention avoids floodingthe pavement being grooved, and possibly an adjoining traveled lane of pavement to which the water would drain, which is hazardous to traffic. It also avoids leav-- ing an incrustation of pavement particles, such as impairs the effectiveness of the grooving and also presents a hazard when dislodged subsequently, as by jet engines. Economy of operation is-effected by recovery of diamonds or other valuable components of the cutter material, as well as by possible use of byproduct particulate pavement material. Other advantages and bene- .fits thereof will accrue and become apparent to those undertaking to practice the invention.

Although a preferred embodiment and certain modiiications thereof have been illustrated and described, it will be understood that other modifications may be made therein, as by adding, combining, or subdividing parts or steps, while retaining at least some of the advantages and benefits of this invention, which itself is defined in the following claims.

1 claim;

1. ln' mobile apparatus for multiple grooving of pavement to improve traction thereon when wet, including cutter means engageable in cutting contact with the pavement at a multiplicity of laterally spaced grooving locations and means for supplying water to outlets near such groovinglocations, the improvement comprising shroud means for enclosing the cutting means above the pavement and for collecting a slurry of particulate pavement material and cutter material formed therein, the shroud having a generally involute transverse cross section and being spaced closer to the cutter means in the forward direction than in the rearward direction.

2. Apparatus for multiple grooving of pavement according to claim 1, including troughs closing the shroud underneath, respectively fore and aft of the c utter means.

i 3. Apparatus for multiple grooving of pavement according to claim 2, wherein the water outlets are located adjacent'the aft trough.

4. Apparatus for multiple grooving of pavement according to'claim 2, including means for pumping slurry from the troughs.

5. Apparatus for multiple grooving of pavement according to claim 4, including means for separating particulate material from the slurry.

6. ln apparatus for multiple grooving of pavement, wherein dislodged particles of dense cutter material cutter means and moving along the pavement to cut a spaced multiplicity of parallel grooves therein, a mobile reservoir of water and conduits for the water from the reservoir to outlets therefor near the cutter means and the grooving locations, shroud :means covering the grooving locations and having a trough therein occupying substantially all the space between the rearward extent of the cutter means and the trailing edge of the shroud means, a conduit from the shroud means to a mobile storage tank for the slurry, and a pump for delivering the slurry collected in the shroud means to the storage tank.

7. Apparatus for multiple grooving of pavement according to claim 6, including means for separating the slurry into respective portions according to relative densities of the 'slurried particles, and means for recovering particles from at least one such portion.

8. Apparatus for multiple grooving of pavement according to claim 7, including means for filtering particles of dense cutter material from onesuch portion.

9. For use in conjunction with mobile apparatus for multiple grooving of pavement, wherein rotation of closely spaced, parallel cutting blades containing reusable abrasive particlesin contactwith the pavement in the presence of water dislodges particles of pavement material from the pavement and reusable abrasive particles from the blades, the dislodged particles forming a slurry with the water, the combination of means for collecting the slurry, means for sepa'ratingparticles from the slurry, and means for separating reusable abrasive particles from pavement particles.

i 10. For'use in conjunction with mobileapparatus for ticles from the blades, the dislodged particles forming a slurry with the water, the combination of means for collecting the slurry and means for reclaiming reusable abrasive particles therefrom.

11. Apparatus according to claim 10, wherein the collecting meansincludes a narrow trough immediately forward of the blades and a wide trough immediately aft of the blades.

12. Apparatus according to" claim 10, wherein the collection means includes troughs located forward and aft of the blades and extending under the furthest forward and aftextent thereof. i

13. Apparatus according to claim 10, wherein the collection means includes a shroud over the blades and extending furtheraft than forward thereof and troughs occupying substantially all of the space forward and aft of the blades at a location below the center thereof.

14. Apparatus according to claim 10, 'wherein the means for reclaiming reusable abrasive particles from the slurry includes at least one hydrocyclonic separator and a settling tank.

15. Apparatus according to claim 10, wherein the means for reclaiming reusable abrasive particles from the slurry is carried on a trailer relative to the mobile apparatus having the rotatable cutter blades.

16. Multiple grooving apparatus for pavement to improve traction thereon comprising closely spaced parallel rotary cutting means adapted to cut parallel grooves in pavement when rotating in cutting contact therewith and thereby to dislodge particles from the and less dense pavement material are slurried together i in cooling water, a driven vehicle for supporting the pavement and abrasive particles from the cutting means, means for supplying water to the cutting means the pavement particles and the abrasive particles from the slurry and from each other. *7 l l 

1. In mobile apparatus for multiple grooving of pavement to improve traction thereon when wet, including cutter means engageable in cutting contact with the pavement at a multiplicity of laterally spaced grooving locations and means for supplying water to outlets near such grooving locations, the improvement comprising shroud means for enclosing the cutting means above the pavement and for collecting a slurry of particulate pavement material and cutter material formed therein, the shroud having a generally involute transverse cross section and being spaced closer to the cutter means in the forward direction than in the rearward direction.
 2. Apparatus for multiple grooving of pavement according to claim 1, including troughs closing the shroud underneath, respectively fore and aft of the cutter means.
 3. Apparatus for multiple grooving of pavement according to claim 2, wherein the water outlets are located adjacent the aft trough.
 4. Apparatus for multiple grooving of pavement according to claim 2, including means for pumping slurry from the troughs.
 5. Apparatus for multiple grooving of pavement according to claim 4, including means for separating particulate material from the slurry.
 6. In apparatus for multiple grooving of pavement, wherein dislodged particles of dense cutter material and less dense pavement material are slurried together in cooling water, a driven vehicle for supporting the cutter means and moving along the pavement to cut a spaced multiplicity of parallel grooves therein, a mobile reservoir of water and conduits for the water from the reservoir to outlets therefor near the cutter means and the grooving locations, shroud means covering the grooving locations and having a trough therein occupying substantially all the space between the rearward extent of the cutter means and the trailing edge of the shroud means, a conduit from the shroud means to a mobile storage tank for the slurry, and a pump for delivering the slurry collected in the shroud means to the storage tank.
 7. Apparatus for multiple grooving of pavement according to claim 6, including means for separating the slurry into respective portions according to relative densities of the slurried particles, and means for recovering particles from at least one such portion.
 8. Apparatus for multiple grooving of pavement according to claim 7, including means for filtering particles of dense cutter material from one such portion.
 9. For use in conjunction with mobile apparatus for multiple grooving of pavement, wherein rotation of closely spaced parallel cutting blades containing reusable abrasive particles in contact with the pavement in the presence of water dislodges particles of pavement material from the pavement and reusable abrasive particles from the blades, the dislodged particles forming a slurry with the water, the combination of means for collecting the slurry, means for separating particles from the slurry, and means for separating reusable abrasive particles from pavement particles.
 10. For use in conjunction with mobile apparatus for multiple grooving of pavement, wherein rotation of closely spaced parallel cutting blades containing reusable abrasive particles in contact with the pavement in the presence of water dislodges particles of pavement material from the pavement and reusable abrasive partiCles from the blades, the dislodged particles forming a slurry with the water, the combination of means for collecting the slurry and means for reclaiming reusable abrasive particles therefrom.
 11. Apparatus according to claim 10, wherein the collecting means includes a narrow trough immediately forward of the blades and a wide trough immediately aft of the blades.
 12. Apparatus according to claim 10, wherein the collection means includes troughs located forward and aft of the blades and extending under the furthest forward and aft extent thereof.
 13. Apparatus according to claim 10, wherein the collection means includes a shroud over the blades and extending further aft than forward thereof and troughs occupying substantially all of the space forward and aft of the blades at a location below the center thereof.
 14. Apparatus according to claim 10, wherein the means for reclaiming reusable abrasive particles from the slurry includes at least one hydrocyclonic separator and a settling tank.
 15. Apparatus according to claim 10, wherein the means for reclaiming reusable abrasive particles from the slurry is carried on a trailer relative to the mobile apparatus having the rotatable cutter blades.
 16. Multiple grooving apparatus for pavement to improve traction thereon comprising closely spaced parallel rotary cutting means adapted to cut parallel grooves in pavement when rotating in cutting contact therewith and thereby to dislodge particles from the pavement and abrasive particles from the cutting means, means for supplying water to the cutting means to cool it and to slurry the dislodged particles, and means for collecting and treating the slurry to separate the pavement particles and the abrasive particles from the slurry and from each other. 